Change in coreboot[master]: libpayload/x86/malloc: Add methods to allocate low memory

[Patrick Rudolph (Code Review)]

Patrick Rudolph has uploaded this change for review. ( https://review.coreboot.org/23583

Change subject: libpayload/x86/malloc: Add methods to allocate low memory
......................................................................

libpayload/x86/malloc: Add methods to allocate low memory

Add implementation of low_malloc to allocate heap below 1MiB.

Change-Id: I5b303863a4a41a07f3b7c01e3e85706ae105ec87
Signed-off-by: Patrick Rudolph 
---
M payloads/libpayload/arch/x86/main.c
M payloads/libpayload/arch/x86/sysinfo.c
M payloads/libpayload/include/stdlib.h
M payloads/libpayload/libc/malloc.c
4 files changed, 80 insertions(+), 0 deletions(-)

git pull ssh://review.coreboot.org:29418/coreboot refs/changes/83/23583/1

diff --git a/payloads/libpayload/arch/x86/main.c b/payloads/libpayload/arch/x86/main.c
index 5f7f505..e5534b8 100644
--- a/payloads/libpayload/arch/x86/main.c
+++ b/payloads/libpayload/arch/x86/main.c
@@ -57,6 +57,8 @@

exception_init();

+	init_low_memory();
+
    /*
     * Any other system init that has to happen before the
     * user gets control goes here.
diff --git a/payloads/libpayload/arch/x86/sysinfo.c b/payloads/libpayload/arch/x86/sysinfo.c
index ddd6550..45b30ff 100644
--- a/payloads/libpayload/arch/x86/sysinfo.c
+++ b/payloads/libpayload/arch/x86/sysinfo.c
@@ -81,3 +81,10 @@

return ret;
 }
+
+void lib_sysinfo_get_memranges(struct memrange **ranges,
+			       uint64_t *nranges)
+{
+	*ranges = &lib_sysinfo.memrange[0];
+	*nranges = lib_sysinfo.n_memranges;
+}
diff --git a/payloads/libpayload/include/stdlib.h b/payloads/libpayload/include/stdlib.h
index 658fe61..f9563c7 100644
--- a/payloads/libpayload/include/stdlib.h
+++ b/payloads/libpayload/include/stdlib.h
@@ -150,10 +150,13 @@
 void *memalign(size_t align, size_t size);
 void *dma_malloc(size_t size);
 void *dma_memalign(size_t align, size_t size);
+void *low_malloc(size_t size);
+void *low_memalign(size_t align, size_t size);
 #endif
 void init_dma_memory(void *start, u32 size);
 int dma_initialized(void);
 int dma_coherent(void *ptr);
+int init_low_memory(void);

static inline void *xmalloc_work(size_t size, const char *file,
    			 const char *func, int line)
diff --git a/payloads/libpayload/libc/malloc.c b/payloads/libpayload/libc/malloc.c
index 595af63..84b310c 100644
--- a/payloads/libpayload/libc/malloc.c
+++ b/payloads/libpayload/libc/malloc.c
@@ -64,6 +64,7 @@
    };
 static struct memory_type *const heap = &default_type;
 static struct memory_type *dma = &default_type;
+static struct memory_type *low_mem = NULL;

typedef u64 hdrtype_t;
 #define HDRSIZE (sizeof(hdrtype_t))
@@ -124,6 +125,57 @@
    return !dma_initialized() || (dma->start <= ptr && dma->end > ptr);
 }

+int init_low_memory(void)
+{
+	uint64_t nranges;
+	struct memrange *ranges;
+	unsigned long long start;
+	unsigned long long size;
+
+	if (low_mem) {
+		printf("ERROR: %s called twice!\n", __func__);
+		return 0;
+	}
+
+	lib_sysinfo_get_memranges(&ranges, &nranges);
+	if (!nranges)
+		return 1;
+
+	start = 0x100000ULL;
+	size = 0;
+	for (size_t i = 0; i < nranges; i++) {
+		if (ranges[i].type != CB_MEM_RAM)
+			continue;
+		if (ranges[i].base > start)
+			continue;
+		if (ranges[i].size < size)
+			continue;
+
+		size = ranges[i].size;
+		start = ranges[i].base;
+	}
+
+	if (!size)
+		return 1;
+
+	low_mem = malloc(sizeof(*low_mem));
+	if (!low_mem)
+		return 1;
+
+	low_mem->start = (void *)(uintptr_t)start;
+	low_mem->end = (void *)(uintptr_t)(start + size);
+	low_mem->align_regions = NULL;
+
+#if IS_ENABLED(CONFIG_LP_DEBUG_MALLOC)
+	low_mem->minimal_free = 0;
+	low_mem->magic_initialized = 0;
+	low_mem->name = "LOW";
+
+	printf("Initialized low memory at [%p:%p]\n", start, start + size);
+#endif
+	return 0;
+}
+
 static void *alloc(int len, struct memory_type *type)
 {
    hdrtype_t header;
@@ -259,6 +311,14 @@
    return alloc(size, heap);
 }

+void *low_malloc(size_t size)
+{
+	if (!low_mem)
+		return NULL;
+
+	return alloc(size, low_mem);
+}
+
 void *dma_malloc(size_t size)
 {
    return alloc(size, dma);
@@ -533,6 +593,14 @@
    return alloc_aligned(align, size, heap);
 }

+void *low_memalign(size_t align, size_t size)
+{
+	if (!low_mem)
+		return NULL;
+
+	return alloc_aligned(align, size, low_mem);
+}
+
 void *dma_memalign(size_t align, size_t size)
 {
    return alloc_aligned(align, size, dma);